Thanks for the link! I had read another article about precipitating it out and it sounded like mucho effort! This makes total sense and seems so simple it's brilliant.

Questions:
1) When have you lowered the pH to a point that you can't swim? I guess a better question is, what are the water conditions under which you shouldn't let people in! I noticed in the article that it talked about 10 year old boys aerating. I personally think it's an excellent excuse for one of those fountains I've been eyeing up ;-)

2) How frequently are you adding acid and testing in step 5? I'm assuming we'd target 100ppm since clearly it's a fill water problem and may be a recurring issue of it creeping up over time. What is the range of pH where this is effective? If I maintain 7.2 and aerate, will I see a drop of TA over time?

I'm thinking that it may be a process best left to the end of the swim season if it means the kids can't use the pool but am super excited that it's such a straight forward effort. I was afraid I was doomed with my hard water forever! I'm still hoping the town puts in softening in the new water treatment plant -- we can hope!!

I'm off to add my CYA and put a dose of bleach in. How do you calculate the dose sizes? I've seen the online pool calculator but curious how others figure it.